Japanese Patent Laid-Open No. 2004-190547 discloses a conventional motor-driven compressor (simply referred to as compressor below). The compressor comprises a housing, an electric driving mechanism, a compression mechanism, and a motor drive circuit. The compression mechanism is driven by the electric driving mechanism to compress a refrigerant. The motor drive circuit drives the electric driving mechanism. The housing includes a housing body and a cover. The electric driving mechanism and the compression mechanism are accommodated in the housing body. The cover is fixed to the housing body. The cover forms an accommodation chamber that accommodates the motor drive circuit between the cover and the housing body. An inverter is employed as the motor drive circuit.
The cover includes a connector portion which is configured to be connected with an external connector. The connector portion includes a pair of metal wires, and an insulating resin for fixing the two wires to the cover. Each of the wires includes a terminal portion that is configured to be electrically connected to the external connector, and a lead portion that electrically connects the terminal portion to the motor drive circuit.
As also described in Japanese Patent Laid-Open No. 2009-295340, each of the wires is obtained by bending a metal flat plate. More specifically, each of the wires includes a flat plate portion having a plate-like shape that extends to a distal end side toward the external connector, and the lead portion that is connected with the flat plate portion on a proximal end side, extends toward the inverter, and also fixed to the insulating resin.
In the compressor, the two wires are subjected to insert molding in the insulating resin to obtain the cover where the two wires are arranged in the connector portion. When the external connector is connected with the connector portion of the cover, the two wires are connected to the external connector. Power can be thereby fed to the inverter from the external connector.
However, in the above conventional compressor, since each of the wires includes the flat plate portion having a plate-like shape, contact area between the flat plate portion and the external connector is not sufficient. Thus, a resistance value between the flat plate portion and the external connector is high, thereby disadvantageously generating heat especially when a high current flows and hindering power saving. When the compressor is mounted to, for example, a vehicle, friction occurs at a contact point between the flat plate portion and the external connector due to vibrations generated while the vehicle is running. Thus, there is a demand for an improvement in durability.
In order to increase the contact area between the wire and the external connector, a wire including a solid round pin may be employed. In this case, however, a manufacturing cost may be increased. Particularly, when the round pin is subjected to plating or welding, the above tendency becomes prominent due to an increase in working steps.
On the other hand, when a wire including a terminal portion having a hollow cylindrical shape is employed as the wire, the insulating resin having fluidity flows into the terminal portion at the time of forming the cover. Thus, a defective product is easily produced.
The present invention has been made in view of the aforementioned conventional circumstances, and an object thereof is to provide a motor-driven compressor which suppresses heat generation, enables power saving, exerts excellent durability, lowers a manufacturing cost, and hardly produces a defective product.